I buy my Gravure Idol stuff with several sites. I think it's pretty easy but DVDs and BDs are pretty expensive in Japan...
cdjapan.co.jp :
This is neowing.co.jp for overseas costumers. There is a lot of items but not much as neowing. I've asked why by mail, they said that they do not want to continue to sell Gravure items because they had troubles with some countries (considerating Image Video as porn) and if there is those kind of items on cdjapan, this is by mistake. This is kinda wired cause they continue to sell it,
http://c.manifo.jp/ (a site with only Gradol powered by CDJapan) still exist even if it's not updated anymore, and, this week, I've received a mail to subscribe to the new Gravure Idol news mail
+ packaging is very good
+ large choice of shipping method
- you can't find all that you want
- can't pay by paypal
yesasia.com :
Do not know if we are still able to buy IV on their site even if they still propose it : I've tried to buy the last Tsukasa Kanzaki and Rin Sasayama in April; It was 2 pre-orders but they sent me a refund saying it was out-off-stock...
+ free shipping available
+ large choice of items
- packaging is not very good (several DVD were in bad condition...)
amazon.co.jp :
Their politic is wired. So much IV are in Adult (even DVDs with under 18 models... ). I guess they want to stop selling IV : some makers' new stuff are not listed anymore... (I've had the chance to buy some items before they go in "adult") :s
- less and less choice
- only DHL
hmv.co.jp/en/ :
The only thing that sucks is that they only ship items by EMS...
+ large choice
+ multi buy reduction
- only EMS
There is also Proxy Shopping Service as tenso/buyee. I've tried some of them. Some time they refused to buy IV items because of the "sexual content" : depending with the appreciation of the one who takes your order. It's better to contact them before making an order.
For example, I've tried JIGS for several month and they finally asked me to stop using their service after I've ordered Rin Sasayama DVDs
Now, I mainly buy on cdjapan, or with proxy shops, on suruga-ya.com and dmm.com.
Edit : CDJapan stopped selling IV DVDs and BDs
Edit 2 : but it was only for few weeks